Hybrid inflator with pop-out diffuser

Description

[0001] The present invention relates to an inflator for use as part of an airbag module and, more particularly, to a hybrid inflator having a pop-out diffuser.

[0002] An airbag module is employed in an automobile for protecting an occupant against injury by deploying an inflated airbag cushion to physically restrain the occupant's body when the automobile encounters a collision. An inflator produces inflation gas for inflating the airbag cushion.

[0003] Some existing inflators are of the hybrid type that produce inflation gas from a combination of stored compressed inert gas and pyrotechnic gas generant which are separated within an inflator housing of the inflator by a first burst diaphragm. Upon initiation of the hybrid inflator, an initiator ignites the pyrotechnic gas generant which creates a hot gas/particulate effluent which ruptures the burst diaphragm and heats the compressed gas.

[0004] The inflator housing includes a diffuser normally fixed to a wall of the housing over an outlet opening defined by the wall. The diffuser defines at least one gas exhaust port, and is separated from the compressed gas by a second burst diaphragm. As the compressed gas is heated the pressure within the inflator housing rises until the second burst diaphragm is ruptured, allowing the heated compressed gas to rapidly exit the inflator through the gas exhaust ports of the diffuser to inflate an airbag cushion of the airbag module.

[0005] A problem, however, is that fragments of the ruptured second diaphragm can partially block the gas exhaust ports of the diffuser and disrupt the designed flow of the heated compressed gas into the airbag cushion. To prevent blockage of the gas exhaust ports, many hybrid inflator include cleaning filters for filtering the gas flow. In addition, because the diffuser extends outwardly from the hybrid inflator, the inflator is awkward to install and awkward to package and ship prior to installation, and the overall size of the airbag module is increased.

[0006] It is therefore desirable to provide a diffuser that does not require a burst diaphragm positioned between the diffuser and stored compressed gas of a hybrid inflator, to reduce the chance of the diffuser being blocked by fragments of the burst diaphragm and obviate the need for a cleaning filter in the diffuser.

[0007] Also advantageous is a diffuser that does not substantially extend outwardly from a hybrid inflator prior to initiation of the hybrid inflator, thus simplifying the installation of the hybrid inflator and the packaging and shipping of the hybrid inflator prior to installation in an airbag module, and providing more space within an airbag module for packing an airbag cushion.

[0008] US-A-5,536,039 discloses a hybrid inflator having a housing with an outer wall defining a compressed gas reservoir with a cylindrical central portion welded therein enclosing an initiator and a combustion chamber from which combustion gases can pass through the compressed gas reservoir via apertures in the central portion. Slidably mounted within the central portion is a pop-out diffuser including a piston having at one axial end, flush with said housing outer wall and welded into one end of the central portion, an end plate with a rupturable seam defining a diffuser plate integral with the piston. Upon actuation, the seam ruptures to allow the piston to slide axially outwards. Diffuse fins on the piston then abut the remaining welded portion of the end plate and define a passage for inflation gases to flow out from the reservoir.

[0009] It is an object of the present invention to provide a hybrid inflator including a simplified diffuser having fewer parts.

[0010] The present invention consists in an inflator housing for use as part of a hybrid inflator, the housing comprising:

A) an outer wall defining a compressed gas reservoir;

B) a pop-out diffuser including;

1) a diffuser plate forming an integral part of the outer wall and defined by a rupturable seam formed in the outer wall and surrounding the diffuser plate, and

2) a diffuser sleeve extending from the diffuser plate into the compressed gas reservoir to a diffuser flange extending radially outwardly from the diffuser sleeve, the diffuser flange having an outer diameter greater than an outer diameter of the diffuser plate defined by said rupturable seam, the diffuser sleeve defining a plurality of gas exhaust ports.

[0011] Upon initiation of the hybrid inflator, the diffuser rupture seam will rupture and form a portal in the outer wall so that the diffuser can extend out of the inflator and diffuse inflation gas for inflating an airbag cushion.

[0012] In one embodiment of the present invention, the outer wall includes an elongated, generally cylindrical sidewall extending from a first end to a second end. A first endwall closes the first end of the cylindrical sidewall and defines an initiator port, and a combustion housing extends from the first endwall to within the cylindrical sidewall. The combustion housing internally defines a combustion chamber extending from the initiator port and communicating with the compressed gas reservoir through an inlet port defined by the combustion housing, and a rupturable burst diaphragm seals the inlet port. A second endwall closes the second end of the cylindrical sidewall, and the diffuser plate of the pop-out diffuser forms part of the second endwall with the diffuser sleeve extending to within the cylindrical sidewall.

[0013] According to another embodiment of the present invention, the inflator housing further comprises a generally cylindrical center tie having an upper end and a lower end. The center tie defines a combustion chamber extending axially inwardly from the lower end, and a diffuser cavity extending axially inwardly from the upper end. The outer wall of the inflator housing includes an upwardly facing concave bottom wall secured to the lower end of the central tie and defining an initiator port providing access to the combustion chamber. A downwardly facing concave top wall is secured to the upper end of the central tie, with an outer edge of the top wall secured to an outer edge of the bottom wall so that the center tie, the top wall and the bottom wall define the compressed gas reservoir. The diffuser plate of the pop-out diffuser forms part of the top wall covering the diffuser cavity, with the diffuser sleeve extending into the diffuser cavity. The center tie also defines an inlet port connecting the combustion chamber with the compressed gas reservoir and an outlet port connecting the compressed gas reservoir with the diffuser cavity, with a rupturable burst diaphragm sealing the inlet port.

[0014] A hybrid inflator according to the present invention is also provided and includes an inflator housing as described above. The inflator housing further has a combustion chamber separated from the compressed gas reservoir by a rupturable burst diaphragm. The hybrid inflator also includes compressed inert gas contained within the compressed gas reservoir of the inflator housing, and an initiator and pyrotechnic gas generant contained within the combustion chamber of the inflator housing. The initiator is operable by a remote collision sensor through an initiator port defined by the outer wall providing access to the combustion chamber.

[0015] The present invention, therefore, provides a new and improved hybrid inflator for an airbag module and, more particularly, provides a new and improved inflator housing for a hybrid inflator. Even more particularly, the present invention provides a pop-out diffuser for a hybrid inflator. The pop-out diffuser is relatively simple and has fewer parts than many existing diffusers. In addition, the pop-out diffuser does not extend outwardly from the hybrid inflator prior to initiation of the hybrid inflator, thereby providing more space within an airbag module for packing an airbag cushion. Furthermore, the pop-out diffuser does not require a burst diaphragm positioned between the diffuser and the compressed gas reservoir of the hybrid inflator, reducing the chance of the diffuser becoming blocked by fragments of the burst diaphragm upon initiation of the inflator and reducing the need for a cleaning filter in the diffuser.

[0016] The invention together with further objects, features, advantages and aspects thereof, will be more clearly understood from the following description taken in connection with the accompanying drawings.

FIG. 1 is a side sectional view of a hybrid inflator including a pop-out diffuser according to the present invention;

FIG. 2 is a side sectional view of the hybrid inflator of FIG. 1 showing the pop-out diffuser extended after initiation of the hybrid inflator;

FIG. 3 is a side sectional view of another hybrid inflator including a pop-out diffuser according to the present invention; and

FIG. 4 is a side sectional view of the hybrid inflator of FIG. 3 showing the pop-out diffuser extended after initiation of the hybrid inflator.

[0017] The same reference numerals refer to the same elements throughout the various figures.

[0018] A hybrid inflator 10 including a pop-out diffuser 12 according to the present invention is illustrated in FIGS. 1 and 2. The hybrid inflator 10 is similar to a hybrid inflator having a tortuous delivery passage shown and described in U.S. Patent 5,423,570 which is assigned to the assignee of the present invention. The hybrid inflator 10 is for use as part of an airbag module, typically a driver side airbag module, and is for providing inflation gas for inflating an airbag cushion of airbag module as is known in the art. The pop-out diffuser 12 according to the present invention remains stored within the inflator 10 prior to initiation of the inflator, as shown in FIG. 1. Upon initiation of the inflator 10, rapidly increased pressure within the inflator causes the pop-out diffuser 12 to pop out or extend out of the inflator as shown in FIG. 2, to allow inflation gases created within the inflator to exit and be dispersed through the pop-out diffuser.

[0019] The hybrid inflator 10 includes a metal inflator housing 14 having a generally cylindrical center tie 16 having an outwardly flanged upper end 18 and an outwardly flanged lower end 20. An upwardly facing concave bottom wall 22 is secured to the lower end 20 of the central tie 16 by weld 24, and a downwardly facing concave top wall 26 is secured to the upper end 18 of the central tie by weld 28. An outer edge 30 of the top wall 26 is secured to an outer edge 32 of the bottom wall 22 by weld 34, and an inflator flange 36 extends radially outwardly from the outer edge of the top wall and defines a plurality of spaced-apart mounting holes 38 for mounting the hybrid inflator 10.

[0020] The top wall 26, the bottom wall 22 and the center tie 16 together define a toroidal compressed gas reservoir 40 surrounding the center tie. The compressed gas reservoir 40 is filled with an inert gas, such as argon or nitrogen, at pressure in the range of 138 to 276 bar (2,000 to 4,000 psi)., and the gas is sealed in the compressed gas reservoir as described below until operation of the hybrid inflator 10. The gas is introduced into the compressed gas reservoir 40 through a fill port 42, which is then welded shut.

[0021] The center tie 16 defines a combustion chamber 44 which extends axially inwardly from the lower end 20 of the center tie, and the bottom wall 22 defines an initiator port 46 providing access to the combustion chamber. The combustion chamber 44 contains a pyrotechnic heat source material 48 generally comprised of boron potassium nitrate (BKNO₃) or other suitable pyrotechnic which produces hot gases used to heat the stored gas. The combustion chamber 44 and pyrotechnic heat source material 48 contained therein is further provided with an initiator squib 50 mounted in a cylindrical plug 52 which seals the combustion chamber at the lower end 20 of the center tie 16. The plug 52 and the squib 50 are secured in position by a beveled plate 54 which is welded to the bottom wall 22.

[0022] The center tie 16 defines an inlet port 56 extending from the combustion chamber 44 into the compressed gas reservoir 40. Prior to operation of the hybrid inflator 10, the compressed gas reservoir 40 is sealed from the combustion chamber 44 by a thin metal rupturable burst diaphragm 58 welded about its perimeter to a stepped portion 60 of the inlet port 56. The diaphragm 58 is backed by a solid plug 62 received in a chamfered seat 64 of the inlet port 56, thereby providing support against the gas pressure for the thin diaphragm. The center tie 16 further defines an outlet port 66 adjacent the upper end 18 thereof leading to a diffuser chamber 68 which extends axially inwardly from the upper end of the center tie. The outlet port 66 is aligned with and diametrically opposed to the inlet port 56 to provide a tortuous flow path as described below.

[0023] The pop-out diffuser 12 includes a circular diffuser plate 70 formed as a unitary part of the top wall 26. The diffuser plate 70 is surrounded by a diffuser rupture seam 72 in alignment with the diffuser chamber 68 of the center tie 16 and separating the diffuser plate from the remainder of the top wall 26. The diffuser rupture seam 72 is in the form of a notch or a thinned outline in the top wall 26 designed to give or break once a predetermined level of pressure is reached within the compressed gas reservoir 40. A cylindrical diffuser sleeve 74 is secured to the diffuser plate 70 with weld 75, and extends downwardly into the diffuser chamber 68 to a radially outwardly extending, continuous diffuser flange 76. The diffuser flange 76 has an outside diameter that is larger than the diameter of the diffuser plate 70. The diffuser sleeve 74 is provided with a plurality of evenly spaced-apart diffuser exhaust ports 78.

[0024] The hybrid inflator 10 functions in the following manner. In response to a signal indicative of a vehicle crash, a control signal is communicated to the initiator squib 50, which is activated. Upon activation, the initiator squib 50 fires, igniting the pyrotechnic heat source material 48. As pressure in the combustion chamber 44 rises and exceeds the pressure within the compressed gas reservoir 40 and the strength of the rupturable burst diaphragm 58, the plug 62 is unseated and the burst diaphragm ruptures. Hot gas and hot particles from the burning pyrotechnic heat source material 48 and initiator squib 50 flow through the inlet port 56 into the compressed gas reservoir 40, heating the compressed inert gas and causing a rapid pressure rise in the reservoir. When the pressure in the compressed gas reservoir 40 exceeds the structural capability of the diffuser rupture seam 72, the diffuser rupture seam ruptures and a portal 80 in the shape of the rupture seam is formed in the top wall 26, allowing the diffuser plate 70 and diffuser sleeve 74 to pop out and extend above of the top wall of the inflator housing 14 through the portal. The operating pressure of the hybrid inflator 10 can vary depending upon many factors including the size of the inflator and the operating conditions. The structural capability of the diffuser rupture seam 72 can be accordingly adjusted by varying the depth and width of the rupture seam. Because the diffuser flange 76 has an outside diameter that is larger than a diameter of the diffuser plate 70 and portal 80, the diffuser flange engages a peripheral portion of the top wall 26 around the portal and prevents the pop-out diffuser 12 from being ejected from the inflator 10. The diffuser flange 76 does not have to be continuous as long as it can not fit through the portal 80. The heated, compressed inert gas is then able to exit the inflator 10 and be diffused through the diffuser gas exhaust ports 78 of the pop-out diffuser 12 to inflate an airbag cushion (not shown, but common in the art). The diffuser gas exhaust ports 78 collectively have less area than the outlet port 66, whereby the gas exhaust ports throttle the flow of gas from the inflator 10 and provide a desired fill rate into an airbag cushion. Thus, the fill rate can be adjusted as desired for particular airbag structures by varying the diameter and/or number of the gas exhaust ports 78.

[0025] The flow path from the combustion chamber 44 to the diffuser gas exhaust ports 78 is tortuous and thereby prevents or substantially minimizes hot particles exiting the inflator 10, as is described in detail in U.S. Patent 5,423,570. A cleaning and/or cooling filter 82 may be provided within the diffuser sleeve 74, if desired and as known in the art; however, only a lightweight filter is required, if at all.

[0026] Referring now to FIGS. 3 and 4, another hybrid inflator 84 also having a pop-out diffuser 85 according to the present invention is shown. This type of elongated hybrid inflator 84 is typically used in passenger-side airbag modules. The hybrid inflator 84 includes an inflator housing 86 having an elongated, generally cylindrical sidewall 88 extending from a first end 91 to a second end 95. A first endwall 90 closes the first end 91 of the cylindrical sidewall 88 and is secured to the sidewall with weld 92, and a second endwall 94 closes the second end 95 of the cylindrical sidewall and is secured to the sidewall with weld 96. A portion 99 of the second endwall 94 also extends radially outwardly from the sidewall 88 and defines a plurality of spaced-apart mounting holes 98 to provide a mounting plate for mounting the hybrid inflator 84 within an airbag module. The first endwall 90, the sidewall 88 and the second endwall 94 define a compressed gas reservoir 100 filled with an inert gas, such as argon or nitrogen, at pressure in the range of 138 to 276 bar (2,000 to 4,000 psi)., and the gas is sealed in the reservoir, as described below, until operation of the hybrid inflator 84. The inert gas is introduced through a fill port 102, which is then welded shut.

[0027] The first endwall 90 includes a combustion housing 104 defining a combustion chamber 106 which extends axially inwardly into the compressed gas reservoir 100. The combustion chamber 106 contains a pyrotechnic heat source material 108 generally comprised of boron potassium nitrate (BKNO₃) or other suitable pyrotechnic which produces hot gases used to heat the compressed inert gas. The combustion chamber 106 and pyrotechnic heat source material 108 contained therein is further provided with an initiator squib 110 mounted in a cylindrical plug 112 which seals the combustion chamber at the first endwall 90. The plug 112 and the squib 110 are secured in position by a circumferential crimp 114 formed in the first endwall 90. The combustion housing 104 defines an inlet port 116 extending from the combustion chamber 106 into the compressed gas reservoir 100. Prior to operation of the hybrid inflator 84, the compressed gas reservoir 100 is sealed from the combustion chamber 106 by a thin metal rupturable burst diaphragm 118 welded about its perimeter to the combustion housing 104 and backed by a solid plug 120 received in a stepped seat 122 of the inlet port 116, thereby providing support against the gas pressure for the thin burst diaphragm.

[0028] The pop-out diffuser 85 includes a circular diffuser plate 124 formed as a unitary part of the second endwall 94. The diffuser plate 124 is surrounded by a diffuser rupture seam 126 separating the diffuser plate from the remainder of the second endwall 94. A cylindrical diffuser sleeve 128 is secured to the diffuser plate 124 with weld 130, and extends downwardly to a radially outwardly extending, continuous diffuser flange 132. The diffuser flange 132 has an outside diameter that is larger than the diameter of the diffuser plate 124. The diffuser sleeve 128 is provided with a plurality of evenly spaced-apart gas exhaust ports 134. A cleaning and/or cooling filter 136 can be provided within the diffuser sleeve 128 if desired.

[0029] Upon initiation of the hybrid inflator 84, the initiator squib 110 is activated and ignites the pyrotechnic heat source material 108. As pressure in the combustion chamber 106 rises and exceeds the pressure within the compressed gas reservoir 100 and the strength of the rupturable burst diaphragm 118, the plug 120 is unseated and the burst diaphragm ruptures. Hot gas and hot particles from the burning pyrotechnic heat source material 108 and initiator squib 110 flow through the inlet port 116 into the compressed gas reservoir 100, heating the compressed inert gas and causing a rapid pressure rise in the reservoir. When the pressure in the compressed gas reservoir 100 exceeds the structural capability of the diffuser rupture seam 126, the diffuser rupture seam ruptures and a portal 138 in the shape of the rupture seam is formed in the second endwall 94, allowing the diffuser plate 124 and diffuser sleeve 128 to pop out or extend out of the second endwall of the inflator housing 86 through the portal. Because the diffuser flange 132 has an outside diameter that is larger than the diameter of the diffuser plate 124 and portal 138, the diffuser flange engages a peripheral portion of the second endwall 94 around the portal and prevents the pop-out diffuser 85 from being ejected from the inflator 84. The heated, compressed inert gas is then able to exit the inflator 84 and be diffused through the gas exhaust ports 134 of the pop-out diffuser 85 to inflate an airbag cushion (not shown, but common in the art) . The gas exhaust ports 134 throttle the flow of gas from the inflator 84 and provide a desired fill rate into an airbag cushion, which can be adjusted as desired for particular airbag structures by varying the diameter and/or number of the gas exhaust ports.

[0030] The present invention, therefore, provides a new and improved hybrid inflator for an airbag module and, more particularly, provides a new and improved inflator housing for a hybrid inflator. Even more particularly, the present invention provides a pop-out diffuser for a hybrid inflator. The pop-out diffuser is relatively simple and has fewer parts than many existing diffusers. In addition, the pop-out diffuser does not extend outwardly from the hybrid inflator prior to initiation of the hybrid inflator, thereby providing more space within an airbag module for packing an airbag cushion. Furthermore, the pop-out diffuser does not require a burst diaphragm positioned between the diffuser and the compressed gas reservoir of the hybrid inflator, reducing the chance of the diffuser becoming blocked by fragments of the burst diaphragm upon initiation of the inflator and reducing the need for a cleaning filter in the diffuser.

Claims

1. An inflator housing (14, 86) for use as part of a hybrid inflator (10, 84), the housing comprising:

A) an outer wall defining a compressed gas reservoir (40, 100);

B) a pop-out diffuser (12, 85) including;

1) a diffuser plate (70, 124) forming an integral part of the outer wall and defined by a rupturable seam (72, 126) formed in the outer wall and surrounding the diffuser plate, and

2) a diffuser sleeve (74, 128) extending from the diffuser plate into the compressed gas reservoir to a diffuser flange (76, 132) extending radially outwardly from the diffuser sleeve, the diffuser flange having an outer diameter greater than an outer diameter of the diffuser plate defined by said rupturable seam, the diffuser sleeve defining a plurality of gas exhaust ports (78, 134).

2. An inflator housing (86) as defined in Claim 1 wherein the outer wall comprises:

1) an elongated, generally cylindrical sidewall (88) extending from a first end (91) to a second end (95);

2) a first endwall (90) closing the first end of the cylindrical sidewall and defining an initiator port, a combustion housing (104) extending from the first endwall to within the cylindrical sidewall, the combustion housing internally defining a combustion chamber (106) extending from the initiator port and communicating with the compressed gas reservoir (100) through an inlet port (116) defined by the combustion housing, a rupturable burst diaphragm (118) sealing the inlet port; and

3) a second endwall (94) closing the second end of the cylindrical sidewall, the diffuser plate (124) of the pop-out diffuser (85) forming part of the second endwall with the diffuser sleeve (128) extending to within the cylindrical sidewall.

3. An inflator housing (86) as defined in Claim 2 wherein a portion (99) of the second endwall (94) extends radially outwardly from the cylindrical sidewall (88) of the inflator housing and defines a plurality of spaced-apart mounting holes (98).

4. An inflator housing (14) as defined in Claim 1 further comprising a generally cylindrical center tie (16) having an upper end (18) and a lower end (20), the center tie defining a combustion chamber (44) extending axially inwardly from the lower end, and a diffuser cavity (68) extending axially inwardly from the upper end, and wherein the outer wall includes:

1) an upwardly facing concave bottom wall (22) secured to the lower end of the central tie and defining an initiator port (46) providing access to the combustion chamber;

2) a downwardly facing concave top wall (26) secured to the upper end of the central tie, with an outer edge (30) of the top wall secured to an outer edge (32) of the bottom wall so that the center tie, the top wall and the bottom wall define the compressed gas reservoir (40), the diffuser plate (70) of the pop-out diffuser (12) forming part of the top wall covering the diffuser cavity, with the diffuser sleeve (74) extending into the diffuser cavity; and

3) the center tie defining an inlet port (56) connecting the combustion chamber with the compressed gas reservoir and an outlet port (66) connecting the compressed gas reservoir with the diffuser cavity, with a rupturable burst diaphragm (58) sealing the inlet port.

5. An inflator housing as defined in Claim 4 wherein the outlet port (66) is substantially diametrically opposed to the inlet port (56) defined by the center tie (16).

6. An inflator housing as defined in Claim 4 or claim 5 further comprising an inflator flange (36) extending radially outwardly from the outer edge (30) of the top wall and defining a plurality of spaced-apart mounting holes (38).

7. An inflator housing as defined in any preceding claim wherein the diffuser sleeve (74, 128) of the pop-out diffuser (12, 85) contains filter material (82, 136).

8. An inflator housing as defined in any preceding claim wherein the diffuser flange (76, 132) is continuous

9. A hybrid inflator (10, 84)comprising:

A) an inflator housing (14, 86) according to any preceding claim containing a combustion chamber (44, 106) separated from the compressed gas reservoir (40, 100) by a rupturable burst diaphragm (58, 118), the outer wall (22, 90) defining an initiator port (46) providing access to the combustion chamber;

B) compressed inert gas contained within the compressed gas reservoir of the inflator housing; and

C) an initiator (50, 110) and pyrotechnic gas generant (48, 108) contained within the combustion chamber of the inflator housing, the initiator being operable by a remote collision sensor through the initiator port defined by the outer wall.

Ansprüche

1. Aufblaseinrichtungsgehäuse (14, 86) zur Verwendung als Teil einer Hybridaufblaseinrichtung (10, 84) mit

A) einer Außenwand, die einen Vorratsbehälter (40, 100) für komprimiertes Gas begrenzt, und

B) einem herausspringenden Diffusor (12, 85), der

1) eine Diffusorplatte (70, 124), die einen einstückigen Teil der Außenwand bildet und von einer zerreißbaren Naht (72, 126) in der Außenwand gebildet wird und die Diffusorplatte umgibt, und

2) eine Diffusorbuchse (74, 128), die sich von der Diffusorplatte in den Vorratsbehälter für komprimiertes Gas zu einem Diffusorflansch (76, 132) erstreckt, der sich radial von der Diffusorbuchse nach außen erstreckt, wobei der Diffusorflansch einen größeren Außendurchmesser als ein Außendurchmesser der Diffusorplatte hat, der durch die zerreißbare Naht definiert ist, wobei die Diffusorbuchse mehrere Gasentleerungsöffungen (78,134) begrenzt, einschließt.

2. Aufblaseinrichtungsgehäuse (86) nach Anspruch 1, worin die Außenwand

1) eine längliche, allgemein zylindrische Seitenwand (88), die sich von einem ersten Ende (91) zu einem zweiten Ende (95) erstreckt,

2) eine erste Endwand (90), die das erste Ende der zylindrischen Seitenwand verschließt und eine Initiatoröffnung begrenzt, wobei sich ein Verbrennungsgehäuse (104) von der ersten Endwand bis in die zylindrische Seitenwand erstreckt, das Verbrennungsgehäuse im Inneren eine Verbrennungskammer (106) begrenzt, die sich von der Initiatoröffnung aus erstreckt und in Verbindung mit dem Vorratsbehälter (100) für komprimiertes Gas durch eine Einlaßöffnung (116) steht, welche durch die Verbrennungskammer begrenzt ist, und ein zerreißbares Diaphragma (118) die Einlaßöffnung abdichtet, und

3) eine zweite Endwand (94), die das zweite Ende der zylindrischen Seitenwand verschließt, wobei die Diffusorplatte (124) des herausspringenden Diffusors (85) einen Teil der zweiten Endwand bildet und wobei sich die Diffusorbuchse (128) bis in die zylindrische Seitenwand erstreckt, umfaßt.

3. Aufblaseinrichtungsgehäuse (86) nach Anspruch 2, worin ein Teil (99) der zweiten Endwand (94) sich radial nach außen von der zylindrischen Seitenwand (88) des Aufblaseinrichtungsgehäuses aus erstreckt und mehrere voneinander beabstandete Befestigungslöcher (98) begrenzt.

4. Aufblaseinrichtungsgehäuse (14) nach Anspruch 1, weiterhin mit einer allgemein zylindrischen Mittelverbindung (16) mit einem oberen Ende (18) und einem unteren Ende (20), wobei die Mittelverbindung eine Verbrennungskammer (44) begrenzt, die sich axial nach innen von dem unteren Ende aus erstreckt, und mit einem Diffusorhohlraum (68), der sich axial von dem oberen Ende aus nach innen erstreckt, und worin die Außenwand:

1) eine nach oben blickende konkave Bodenwand (22), die an dem unteren Ende der mittigen Verbindung befestigt ist und eine Initiatoröffnung (46) begrenzt, welche Zugang zu der Verbrennungskammer liefert,

2) eine nach unten blickende konkave obere Wand (26), die an dem oberen Ende der mittigen Verbindung befestigt ist, wobei eine Außenkante (30) der oberen Wand an einer Außenkante (32) der Bodenwand so befestigt ist, daß die mittige Verbindung, die obere Wand und die Bodenwand den Vorratsbehälter (40) für komprimiertes Gas begrenzen, die Diffusorplatte (70) des herausspringenden Diffusors (12) Teil der oberen Wand bildet, die den Diffusorhohlraum bedeckt, und die Diffusorbuchse (74) sich in den Diffusorhohlraum erstreckt, und

3) die mittige Verbindung, die eine Einlaßöffnung (56) begrenzt, welche die Verbrennungskammer mit dem Vorratsbehälter für komprimiertes Gas verbindet, und eine Auslaßöffnung (66) begrenzt, die den Vorratsbehälter für komprimiertes Gas mit dem Diffusorhohlraum verbindet, wobei ein zerreißbares Diaphragma (58) die Einlaßöffnung abdichtet, einschließt.

5. Aufblaseinrichtungsgehäuse nach Anspruch 4, worin die Auslaßöffnung (66) im wesentlichen diametral gegenüber der Einlaßöffnung (56) liegt, welche durch die mittige Verbindung (16) begrenzt ist.

6. Aufblaseinrichtungsgehäuse nach Anspruch 4 oder Anspruch 5, weiterhin mit einem Aufblaseinrichtungsflansch (36), der sich radial nach außen von der Außenkante (30) der oberen Wand erstreckt und mehrere voneinander beabstandete Befestigungslöcher (38) begrenzt.

7. Aufblaseinrichtungsgehäuse nach einem der vorausgehenden Ansprüche, worin die Diffusorbuchse (74, 128) des herausspringenden Diffusors (12, 85) Filtermaterial (82, 136) enthält.

8. Aufblaseinrichtungsgehäuse nach einem der vorausgehenden Ansprüche, worin der Diffusorflansch (76, 132) kontinuierlich ist.

9. Hybridaufblaseinrichtung (10, 84) mit:

A) einem Aufblaseinrichtungsgehäuse (14, 86) gemäß einem der vorausgehenden Ansprüche, welches eine Verbrennungskammer (44, 106) enthält, die von dem Vorratsbehälter (40, 100) für komprimiertes Gas durch ein zerreißbares Diaphragma (58, 118) getrennt ist, wobei die Außenwand (22, 90) eine Initiatoröffnung (46) begrenzt, welche Zugang zu der Verbrennungskammer bietet,

B) komprimiertem Inertgas, welches in dem Vorratsbehälter für komprimiertes Gas des Ausblaseinrichtungsgehäuses enthalten ist, und

C) einem Initiator (50, 110) und einem pyrotechnischen Gaserzeuger (48, 108), der in der Verbrennungskammer des Aufblaseinrichtungsgehäuses enthalten ist, wobei der Initiator durch einen entfernten Kollisionssensor über die Initiatoröffnung betätigbar ist, welche durch die Außenwand begrenzt ist.

Revendications

1. Boîtier (14, 86) d'organe de gonflage, destiné à être utilisé comme élément d'un organe de gonflage hybride (10, 84), le boîtier comprenant :

A) une paroi externe qui délimite un réserve (40, 100) de gaz comprimé,

B) un diffuseur éjectable (12, 85) qui comprend :

1) une plaque (70, 124) de diffuseur qui est solidaire de la paroi externe et délimitée par une liaison cassable (72, 126) formée dans la paroi externe et entourant la plaque de diffuseur, et

2) un manchon (74, 128) de diffuseur qui dépasse de la plaque de diffuseur dans le réservoir de gaz comprimé vers une bride (76, 132) de diffuseur qui s'étend radialement à l'extérieur du manchon de diffuseur, la bride de diffuseur ayant un diamètre externe supérieur au diamètre externe de la plaque de diffuseur délimitée par la liaison cassable, le manchon de diffuseur délimitant plusieurs orifices d'échappement de gaz (78, 134).

2. Boîtier (86) d'organe de gonflage selon la revendication 1, dans lequel la paroi externe comporte :

1) une paroi latérale allongée (88) de forme générale cylindrique qui s'étend d'une première extrémité (91) vers une seconde extrémité (95),

2) une première paroi d'extrémité (90) qui ferme la première extrémité de la paroi latérale cylindrique et qui délimite un canal d'amorce, un boîtier (104) de combustion qui s'étend de la première paroi d'extrémité vers l'intérieur de la paroi latérale cylindrique, le boîtier de combustion délimitant à l'intérieur une chambre de combustion (106) qui s'étend depuis le canal d'amorce et qui communique avec le réservoir (100) de gaz comprimé par un canal d'entrée (116) délimité par le boîtier de combustion, un diaphragme cassable (118) d'éclatement fermant de manière étanche le canal d'entrée, et

3) une seconde paroi d'extrémité (94) qui ferme la seconde extrémité de la paroi latérale cylindrique, la plaque de diffuseur (124) du diffuseur éjectable (85) faisant partie de la seconde paroi d'extrémité avec le manchon de diffuseur (128) qui s'étend vers l'intérieur de la paroi latérale cylindrique.

3. Boîtier (86) d'organe de gonflage selon la revendication 2, dans lequel une partie (99) de la seconde paroi d'extrémité (94) s'étend radialement vers l'extérieur de la paroi latérale cylindrique (88) du boîtier d'organe de gonflage et délimite plusieurs trous espacés de montage (98).

4. Boîtier (14) d'organe de gonflage selon la revendication 1, comprenant en outre un tirant central (16) de forme générale cylindrique ayant une extrémité supérieure (18) et une extrémité inférieure (20), le tirant central délimitant une chambre de combustion (44) qui s'étend axialement vers l'intérieur de l'extrémité inférieure, et une cavité de diffuseur (68) qui s'étend axialement vers l'intérieur depuis l'extrémité supérieure, et dans lequel la paroi externe comporte :

1) une paroi inférieure concave (22) tournée vers le haut, fixée à l'extrémité inférieure du tirant central et délimitant un canal d'amorce (46) donnant accès à la chambre de combustion,

2) une paroi supérieure concave (26) tournée vers le bas, fixée à l'extrémité supérieure du tirant central, le bord externe (30) de la paroi supérieure étant fixé à un bord externe (32) de la paroi inférieure afin que le tirant central, la paroi supérieure et la paroi inférieure délimitent le réservoir (40) de gaz comprimé, la plaque de diffuseur (70) du diffuseur éjectable (12) faisant partie de la paroi supérieure qui recouvre la cavité de diffuseur, le manchon de diffuseur (74) s'étendant à l'intérieur de la cavité de diffuseur, et

3) le tirant central délimitant un canal d'entrée (56) qui raccorde la chambre de combustion au réservoir de gaz comprimé et un canal de sortie (66) qui raccorde le réservoir de gaz comprimé à la cavité de diffuseur, un diaphragme cassable d'éclatement (58) fermant le canal d'entrée de manière étanche.

5. Boîtier d'organe de gonflage selon la revendication 4, dans lequel le canal de sortie (66) est pratiquement diamétralement opposé au canal d'entrée (56) délimité par le tirant central (16).

6. Boîtier d'organe de gonflage selon la revendication 4 ou 5, comprenant en outre une bride (36) d'organe de gonflage qui s'étend radialement vers l'extérieur depuis le bords externe (30) de la paroi supérieure et délimite plusieurs trous espacés de montage (38).

7. Boîtier d'organe de gonflage selon l'une quelconque des revendications précédentes, dans lequel le manchon de diffuseur (74, 128) du diffuseur éjectable (12, 85) contient un matériau de filtre (82, 136).

8. Boîtier d'organe de gonflage selon l'une quelconque des revendications précédentes, dans lequel la bride de diffuseur (76, 132) est continue.

9. Organe de gonflage hybride (10, 84), comprenant :

A) un boîtier (14, 86) d'organe de gonflage selon l'une quelconque des revendications précédentes, contenant une chambre de combustion (44, 106) séparée du réservoir de gaz comprimé (40, 100) par un diaphragme cassable d'éclatement (58, 118), la paroi externe (22, 90) délimitant un canal d'amorce (46) donnant accès à la chambre de combustion,

B) un gaz inerte comprimé contenu dans le réservoir de gaz comprimé du boîtier d'organe de gonflage, et

C) une amorce (50, 110) et un matériau pyrotechnique générateur de gaz (48, 108) logés dans la chambre de combustion du boîtier d'organe de gonflage, l'amorce pouvant être commandée par un capteur distant de collision par l'intermédiaire du canal d'amorce délimité par la paroi externe.

Drawing